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Chimney Flashing Repair in South Unionville, Markham

Professional chimney flashing repair in South Unionville, Markham — 24 hour response, licensed & insured.

Call (437) 475-2233
24 hour response
Licensed & insured
OEM parts on the truck

Where your chimney meets the roof in South Unionville, Markham is the single most leak-prone spot on your entire home. Proper chimney flashing has two layers — step flashing woven into the shingles and counter-flashing tucked into the brick mortar joints. When either fails, water tracks straight into the wall.

Why chimney flashing repair matters in South Unionville, Markham

Two-Layer System

Real chimney flashing is a two-part system. Anyone offering to 'just caulk it' is selling you a 12-month fix.

Mortar Cut Matters

Counter-flashing must be cut into the mortar joints — not surface-mounted. Surface-mount flashing on a chimney lasts one winter.

Ice And Water Shield

A proper chimney rework includes ice-and-water membrane under the flashing for a redundant seal.

Our chimney flashing repair process

  1. 1

    On-Site Assessment

    We walk the exterior in South Unionville, Markham, document current condition with photos, and identify every failure point before quoting.

  2. 2

    Written Quote

    You get an itemized estimate — parts, labour, timeline — before any work starts. No surprises.

  3. 3

    Professional Repair

    Our crews use manufacturer-approved materials and industry-standard techniques. Every job is fully insured.

  4. 4

    Cleanup & Verify

    We haul away debris, sweep the work area, and walk the finished job with you before signing off.

  5. 5

    Warranty

    Every job in South Unionville, Markham carries a written labour warranty and full manufacturer coverage on materials.

Common findings in South Unionville, Markham

  • Surface-mounted counter-flashing pulling away from brick
  • Rusted galvanized flashing from years of moisture
  • Missing kick-out flashing at the roof-wall junction
  • Caulk-only 'repairs' from prior contractors

What you get

Real Craftsmanship

Experienced tradespeople in South Unionville, Markham — not day labour — on every job.

Fair, Upfront Pricing

Written quotes before we start. No day-of surprises.

Peace Of Mind

Licensed, insured, and warrantied. If something isn't right, we come back.

Chimney Flashing Repair reviews in South Unionville, Markham

4.9 average from 743 verified customer reviews
Level 2 for a house sale
Recorded the whole flue on video for the buyer's agent. The chimney line item stopped being a negotiation point the same day.
Tom H. - Markham - 2026-04-03
Explained the pricing upfront
Quoted over the phone, confirmed on site before starting, and the final invoice matched exactly. Refreshing in this trade.
Simone R. - Scarborough - 2025-09-27
Camera scan caught a cracked tile
Previous company swept and said everything was fine. Diamond ran a camera and showed me a cracked liner tile on screen. Glad I got the second opinion.
Marta S. - Mississauga - 2025-11-30
Post-fire inspection
Small flue fire in January. They inspected, documented the damage, and coordinated the report with my insurer without me chasing anyone.
Daniel K. - North York - 2026-05-02

FAQ

Why did my flashing fail?

Almost always because it was surface-mounted and caulked instead of cut into the mortar.

Do you cut into the brick?

Yes — that's the only way to do this repair properly. It's called a reglet cut.

Timeline?

Most chimney re-flashing jobs are a same-day, one-crew job.

Book your chimney flashing repair today

24 HOUR RESPONSE GUARANTEED — call now to lock in a slot in South Unionville, Markham.

Call (437) 475-2233

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